def hello():
    print('Hello World')
    hello()
        Hello World



def add():
    a = 3
    b = 5
    s = a + b
    print(s)
    return a
c = add()
print(c)


def add(a, b):
    print(a + b)

add(1,3)

a = 1
b = 3
add(a,b)

add(2 * 3, 4 * 5)

c = 3
add(8, c * 3)

def score(a,b,c):
    print('张三成绩为:',a)
    print('李四成绩为:',b)
    print('王五成绩为:',c)

def reg(name, age, sex="女"):
    print('姓名:{} 年龄 {} 性别: {}'.format(name,age,sex))

    reg('张三',20)
    reg('李四',21,'男')